FateTouhou zero
by tteerit9648
Summary: In the many parallel worlds, there has been an infinite amount of bloodied war between a servant of seven class in the holy grail war. There has been a lot of blood, sweat, and tear. A single wish that every master strives for is what make this war possible. But one evil that could even top Angra Mainyu has been awoken and causing the 4th grail war to change drastically.
1. Chapter 1 Servant summoning

**A/n: Now this is a story that has been on my mind for a long time but never actually gets to write it because of work and stuff. But now that I got time to write it. It turns out to be harder than I thought it would be. Not a native speaker by the way, so if you felt that my fanfic is unreadable, please say so.**

...

Chapter 1: Servant summoning

The holy grail war, a war between servants of seven class. Each competes in a battle for life and death with their masters to win only one thing, their wishes. Every participant in the war has their own ideal and belief that they want to achieve by any means necessary. Whether it's going to be world peace or to protect someone or to be recognized. These people all have their own ambition to fulfill.

Usually, in these countless parallel universes. The holy grail war is bound to have a servant from historical legends battle each other in these bloodbath battles. This 4th grail war of Fuyuki is of no exception. But in this world, there's something extraordinary happening. Something sinister that could even top humanity greatest evil. An incomprehension evil that lurks in the shadow. Now that's evil finally awoken, A servants from entirely different legends will all gather at Fuyuki tonight and it's going to become a war on a level far beyond any of them could anticipate.

…..

Kotomine Kirei was speechless.

On the summoning circle, sat the young girl, look to be no more than 10 years old. She wore a silly black hat with a yellow bow on it with a bright yellow shirt. What's got his attention, however, is the closed eye in the middle of her shirt. It looks somewhat like it could be one with her and yet it not. But more importantly, where is Hassan.

"Hey, there! Could you be my master, I wonder" She was very energetic, that's for sure.

"Yes, I am. Are you Assassin?"

"Am I Assassin? I don't know" What?

"Kirei, what's the meaning of this." Risei who has been quiet the whole time due to shock has spoken for the first time. To be honest, he also doesn't even know what's going on. He was supposed to summon the Hassan. Not some little girl of some unknown origin. How about her stat then?

"Hm, that's weird."

"What's wrong Kirei? You can't read her stat or something?"

" No, father. Her stat was outstanding. But her presence concealment level is at EX rank. She may be the best Assassin we can ever get in this war. What I think is weird is the fact that she was not even the Hassan, but she's this good?"

"That's doesn't matter. What matter is that this girl can be useful to us. Go and make preparation."

"Yes, sir."

…..

In the present day

Waver Velvet was very angry. He put his time and effort into creating that research. Research that takes a challenge to question magus mentality. Most magus thinks that people are born magus not the other way around. He feels different. He believes that if a person tries hard enough, they can become an ideal magus that everyone could look up to.

But his teacher, Kayneth, disagreed and trampled upon everything he lives for. He even humiliated him in front of all those peoples. Everyone laughs at him like he was some fool. But that will change. He will prove to everyone that his research was correct. He will finally get the recognition he deserves.

At least that's what he thought when he finally stole the artifact from his teacher. This artifact used to be a piece of clothing of Alexander the great, a king of the conquerer. He thought he was finally winning at something. But the person standing in front of him is, stunning, to say the least.

"Yo! Man. Are you my master or what?"

A person stands in front of him have an appearance of a witch. That's right, a freaking witch! Did he just summon a caster? Did he just fail? how is he supposed to face his teacher after this!

"Um, are you caster?"

"It would be so much cooler if I am summoned to that class, but unfortunately, I am a Rider, ze!"

"Oh, so you're a Rider. You look like a witch though."

"That's cuz I am freaking witch, ze!"

This war suddenly seems to be a lot harder for Waver, for both his mind and body.

….

Kariya Matou is a very unlucky man, or at least that's what it feels like. After he disgusted in general practice of magus in the Matou family, he decided to run away, run far away from all this madness, run far away from his supposed responsibility. But when he returns, he found out that Zouken, his father, has chosen to adopt Sakura as his own family. But he knows that he only wants a suitable heir for Matou family.

That's why he made a deal with that man. To win the holy grail war and bring back the holy grail back to his father in exchange for Sakura freedom.

But that poses a problem, he is not very good at being a mage due to lack of any kind of formal training. But he will save Sakura no matter what. Even if he must endure this constant pain of all these noises cracking inside his head, he has no choice but to move forward Sakura freedom.

Right now, however, he already finished summoning a servant class berserker. A class considers to be strongest but also very costly in term of energy. But what he gets surprised both him and Zouken a lot.

When the smoke cleared. There appears to be a blazing fire hotter than any volcanoes. In fact, just from the heat alone could vaporize the floor underneath that "thing." But just as fast as it came, a fire dies down.

Reappear instead is the woman look to be in her late teen. She wears what seem to be a white shirt and what appears to be a red bow on her head. What's he wonders though is that this woman doesn't look like a mad servant all? Even if she looks like she was could kill anyone at this moment.

"Tch, how annoying. Who summons me?" She sighed.

"Yes, I am your master."

"Hah! How disappointing. I thought you might summon something good after all but in the end, summon a little girl is the best of your ability as a magus. You are a disgrace, Kariya."

He couldn't deny that. If he couldn't win this war, he doesn't even know what will happen to Sakura. An innocent little girl with a bright future ahead of her. He deserves to be called a fail because he couldn't even free a give a little kid like her to have a chance to look at how beautiful this world is. He's reek of fails just by standing here between his father and his servant. Both of their eyes are looking at him in silence.

"Hey, who do you think you are anyway. Do you think you have a right to judge his performance when you're just standing there doing nothing? If you're so good, why don't you participate in the war yourself? I'm sure that your "majesty" would be better off than this retard, right?"

"Hm! I don't need to. You see, he and I make a deal. For him to gain something, he must find a way to gain something of equally important. That is how this world works little gir-."

*Smash

Kariya didn't know what just happen. One moment his father is standing right behind him but in the next moment his father body is already vaporized without leaving a trace. Except some of the worm that's good enough to escape the raging fire that chases it across the room.

"You know what I think about you? You're a fucking asshole and reminded me of a certain old bitch. But that's beside the point. Take this as a warning because I don't have any idea about what would happen to your "deal" with him if you die. Remember this though, if you mess with my master again. What kind of immortality you may have, it will not save you from my rage."

She's turned, and her face softens lightly. What he saw in her eyes is the eyes of pity. The eyes that have gone through hell and come back stronger. When he looks at her, he feels a little bit of relief.

"Now that's out of the way. Are you my master."

Thus, began Mariya Matou first step into a war of blood and tears to save one innocent girl. To him, freeing that girl was more important than anything else in this world. Now that he got a servant of significant power. He will make that a reality.

…..

Emiya Kiritsugu was sure that he could do anything to achieve his dream of world peace. A world where everyone could live in peace without suffering. In all of his life, he has been taught the opposite. To save something, you must sacrifice something else. That is an undeniable fact that not even him could deny it. But here it is, his chance at salvation, his chance to save everyone.

He even got an Avalon. A catalyst that said to be able to summon King Arthur, the king of knight, who was considered to be in the most potent class. But what he got was not what he signs up for.

"Ha ha ha! Hello, world! Who might be my master?" The first thing he heard is an arrogant voice of some girl he has no idea of"

"WHAT IS THE MEANING OF THIS!" he suddenly shouts.

"Whoa man, calm down. I know that I'm popular, but lets me introduce myself first. For I am servant Saber, and I came down here to give this blessing of my presence in mortal realm again!"

She has an appearance of a little girl, look no older than 15 at best. She wore what looks like a white button-up blouse with a red bow at the collar. A dark red eye, blue hair with a peachy black hat.

"Okay, let me rephrase that. Who are you supposed to be? You shouldn't be the one that gets summon."

"Hm, you don't know about me? Man, the outside world must be so much worse than I anticipated" she sighed in defeat.

"No, let me ask you again. WHO ARE YOU?"

"How about I ask you who you are instead? HOW ABOUT THAT? HAH!"

(I am not going to get a straight answer out of this one. I should check out her stat first before we can go anywhere else.)

Hm, that stat is… quite absurd, to be honest. First off, despite her strength and noble phantasm being quite high. Her every stat except agility is at A rank or higher. This girl might be what he needs to help bring him closer to that ideal than he initially thought.

But first off, he needs to confirm something first.

"Saber, what is your wish for the grail?"

"My wish?"

"Yes, Saber. If we are to work together, I must know your end-goal so I will know that you will not use your wish for an evil idea."

Her face suddenly stiffens. Her breath started to get rough. She was silent for a couple minutes or so, looking down in shame. Suddenly, there was a voice, speaking a voice full of uncertainty.

"W-what do you consider "evil" anyway?"

"What was that?" He started to get irritated at this girl.

"I-is your idea of evil is a person who does something that negatively affects a lot of people, regardless of their reason. I-is it considers to be an evil thing to do if you're ready to sacrifice everyone in the whole world for you to save someone you love? If that is your idea of evil then, I'm afraid that we may never be going to get along. E-even if peoples say that I am a selfish bitch, even if people don't accept what I did. But in my heart, I believe that I was doing the right thing for myself. E-everything I have done so far may be considered evil. But I refuse to change my destination, not now, not ever."

They both stared at each other for some time after that. There was only silence between the true until Irisviel broke the silence.

"Now now you two, I think that we can discuss our ideology later. For now, we should go and prepare a room for you right? Saber?"

"Y-yeah you're right Iriviel. Saber, you can go with Irisviel to find your room for a night. We can discuss this later."

Saber suddenly jerk her head as his proclamation of dismission to her room and did a 180 switch on her personality again.

"Woah man! This is what I'm talking about. A nice bed to accompany my greatest return!"

"Yes! It's nice, isn't it? Especially when you have someone else to accompany you in bed." Irisviel joined in her craziness.

"Hahaha! That's just nic- wait, did you just?"

"Okay! Come on Saber, let's go to your room!"

After they left Kiritsugu alone in the hall. He started to think about what Saber told him. About his ideal to sacrifice even his wife to save more people in the world. Is he still consider a good human being? Would people be seeing his action as a betterment for the society at large? He honestly doesn't know. But his conviction is already set in stone since that day, and he will not abandon his hope of becoming a hero of justice go to waste by just a little disagreement with his servant.

(Just watch me, Saber. I will prove to you that my path is the right one for me and humanity)

A world full of a peaceful smile on everyone face. That image is still lingering in Kirisugu mind. Thus, at this point in time, he swore silently. That he would make that a reality no matter what obstacle he may face. Not even Saber.

…..

Tokiomi Tohsaka was kinda impressed, to be honest.

Rather than one of many Hassan's, what he got was an unknown little girl with an impressive presence concealment skill. At first, he was very skeptical of the ability of this new servant, but that doubt soon dissolve into confident. What he saw was no joke. Assassin was so good that she is able to infiltrate his mansion without him noticing.

The first time he notices was when Assassin came back to a mansion with a couple of candy in her hands. This lead Tokiomi to believe that she could get in and out without alerting the alarm. It's like her existence was completely vanish into nothingness. This could be useful in infiltration or assassination job.

But now is the most crucial part of his plan, a summoning of a king of heroes, Gilgamesh. He even has a skin that was first shed by a snake as a catalyst. Nothing could go wrong from here.

But oh how wrong he was.

When the smoke clears, many eyes were appearing one after another like a portal into an incomprehensible realm. It's like he was looking at the root of everything by himself for only just a moment. But that moment was enough for him, a man who takes pride in his composure afraid for the first time. Even Kirei and Risei couldn't hide their fear.

Tokiomi suddenly feels relieved after the terror was over. But instead there was a ripping hole in space rupturing the very fabric of reality before his eyes and what came out of there, was a woman looking in be in her mid-20s.

She has a long blonde hair, purple eyes. She wore a purple dress mix in with a pink mob cap. Peoples in the room couldn't speak a single word to this abnormality they feel from this thing that decides to appear before them.

"Hoh, I was kinda expecting it to happen eventually but not this soon. Oh well, this has to make do."

"A-are you Archer and w-where are Gilgamesh?" He stumbles for the first time in his life. He can't help it, even now that unperceivable fear is still brewing up in him at each second pass.

"That guy? He wasn't going to come you know. This isn't his time to shine after all ~. "

Tokiomi have no idea what she's talking about. But one thing is clear, he summons this monster instead of Gilgamesh. But it wasn't like he is unhappy with the current situation. In fact, he can feel an infinite power emitting from the radiant of that monster. It wasn't like anything he ever feels before. Is this what it feels like to have a glance at the roots.

"Oh, you didn't have to react so disgust by me you know? Don't you care about my maiden heart at all! You're a meanie!" She suddenly drops down on to the floor and weeps intensely despise everyone who stares at her without taking off their eyes due to how unbelievable the entire situation was.

"Hey, Kirei. What in the world?"

Kirei shrug. "I have no idea."

The air in the room started to get cold when no one reacts. Suddenly Archer head jerks off from the floor and her facial expression return to that of a constantly smirking. It was like all of this was a game to her.

"Man ~ Did you just take me seriously, I'm just kidding ~ "She teased. "But now that we already have our fun, you are my master correct?"

"Yes, I am" He straightens his body to regain a little bit of his confidant. He knows that this servant in front of him is not a normal one by any means. He needs to follow his instinct and respect her as much as he can. So, he bows to her.

"Even if I am your master, you are the one who should stand above me milady. So shall we start our journey to victory as of this moment milady?"

"Oh~ you are flattering me. But all right, I have my fun. State what you think is the best course of action."

"Of course, milady."

….

Thus, Archer, one of the most dangerous players in a many parallel world version of this war. Have been swap with a person with equally precarious existence. How will this war play out? No one knows, but everyone was ready to walk toward that wish they need to make it their reality by any means necessary. In the other side of the grail, however, there existed something far more sinister than any of them realized.

...

 **A/N: If you thought that Tenshi was kinda OCC, it will be explained in due time.**


	2. Chapter 2 Preparation for war

**A/N: This chapter was finished faster than I thought.**

Chapter 2: Preparation for war

Waver velvet was having a tough time with his servant. Not only was he summon a witch in a rider class instead of caster. Rider is also having a little bit of stealing tendency. Every time they pass a library, Rider will ask him if she could go in there and came back with a lot of books. When he asks "What are you doing in there? Rider." She replied with "Borrowing a book, ze!" But he knows that she didn't "Borrow" because there is no registration of borrowed book anywhere inside.

Rider said that she needs as much book as she wants because, to win this game she needs to have a knowledge of an outside world as much as possible. If the book she has is about geography or any real-life knowledge that is, but all he sees was a massive ton of fantasy and sci-fi book. In fact, as of this moment, they already return to his temporary house and laze around doing nothing except reading and watch TV.

At first, he was skeptical of his servant, but now he was sure that this servant is the most useless person he ever comes across, she can't even clean her shit right. Immediately after she's done with one book, she moves on to another without a care in the world. This irritated him to no end.

"Rider! When will you start to clean your shit! I have to work off my ass just to clean the mess you made, and we still haven't fight anyone yet! I thought that we need to win the war!"

"Oh, stop being an ass about it. I know what I'm doing, ze. I'm just waiting for a right time, ze."

"Rider, do you have a plan in mind?"

"Let's see here, I admit that my ability as a rider is pretty good, ze. But I don't know what power our opponent has or what they had in store. Going out there and showing off my ability too fast would be suicide for me, so I let them assume all they want about my ability, ze!"

That's true, other masters should have no idea what rider can do yet, and neither does he. Since the start of the war, Rider hasn't shown him any kind of supernatural ability as a servant yet. What she does show him are all the actions that human being could do. So, this is why she keeps quiet about it.

"There is another thing I'm curious about though Rider, what is your wish for the holy grail."

"Why do you ask?"

"Well, I don't think I have that many ambition or ideas about what I should do if I end up winning. My only goal right now was to get my recognition from the magic community. They think that I am weak, I am just a nobody without talent. But I hope to prove them wrong by bringing the grail back with me. I hope that you could give me any ideas."

"Hm, it's not like I don't understand you, ze. I do, I really do. You know, when I was starting practiced magic, nobody ever actually has any kind of hope for me. They say that a human should never act like one of those monsters and should live my life as a human, even my father. But that beside the point, what I want to tell you is never give up in magic, ze. You should be able to reach your goal eventually."

Waver feels somewhat glad that there is someone in this world who honestly gave him advice instead of "you should give up and accept who you are" without any kind of encouragement. He keeps getting a laugh from his fellow classmates as much as it is, he will keep getting ridicule every day if he does not change. Even if his servant word was only just a simple word of encouragement to move forward, that was enough for him to know that there is someone who believes in him.

"Thank you, rider."

"No problem, ze!" a grin appears on her lip and suddenly dies down "But you did ask me about my wish correct?" He nodded, and she continues "Hm…I don't know if this is going to be understandable to you but what I want is getting back to being human, ze. Living my life as an everyday people, having a friend, go drinking, that kind of stuff, ze. I have no other things I want."

"You only want to live as a human?"

"Well, that's one wish, ze. But my other wish has no way to make it possible without killing a lot of people in the process, ze. Even if I want that wish to come true as much as it is. I can't live with myself knowing that I fucked up the entire world over you know? Ze."

Even Waver himself who is a Magus doesn't think that he has enough what it takes to screw the entire world to get what he wants. Also if that action brings the world a positive consequence in the long run. He doesn't think he can sleep every night without having a nightmare. That only serves to solidifies the fact that he genuinely has no magus mentality in himself, he was something else that exists between both magus and human. But then…

*Smack

Rider suddenly slams her book shut which scares the hell out of Waver.

"Man, that book was so great, ze! Hey, Waver, do you know anywhere else I can borrow a book?"

Oh boy, this is going to be another long day isn't it, sighed Waver.

…..

Fill, fill, fill'er up, fill…

"Repeat four times, wait, was it five times? Um… destroy each when filled, is it?"

Fill, one. Fill, two. Fill, three. Fill, four. Fill, five.

"Alright! That makes it five times. Okay!"

Ryuunosuke Uryuu was a very busy man. Today was like the typical day for him. Go to work and stay with his customer to discuss business with him. But this time, he also brought his book left from his family to read for his client too. If they are listening, that is.

"…At all tree murder scenes, a mysterious pentagram drawn with the victims 'blood was found."

"Maybe I went a little too far…"

*TRUCK

As he said that, there was a sound of something hit the floor. It was one of his customers that require his service today. Too bad, they didn't survive.

Behind the crouch, however, was a little kid. Look to be no older than ten years old. Have his hand tied and mouth covered to prevent his escaping. It was Ryunnosuke's greatest pleasure to watch him twist with every move he takes.

"Hey kiddo, do you believe in the demon? Newspaper, TV, Radio, they all say that I am a demon. But, if a demon is real, wouldn't it be a huge insult to them?"

He saw fears start to be brimming up inside a kid eyes at every word he spoke. For Ryunnosuke, this was like a play to him. He was an actor waiting to be watched by the viewer, they gave him a reaction, and he tries to please them as much as he can.

"Hey, if a demon did appear, would you die for me?"

Then he feels an intense pain brew up in his right hand, it seems to be a mark of some kind. A tattoo maybe? What got his attention the most was the smoke that fills up the entire room, however.

Did he really summon a demon? That's so cool.

What behind the smoke screen, is a woman look to be very weak and frail. She has a purple hair with pink pajamas as her choice of cloth. Her purple eyes dart around the room looking at his art. She must be fascinated by his work!

"Might you be my master perhaps? You got quite a "Hobby" there."

"Um, nice to meet you. My name is Ryunnosuke. My hobby is killing, especially a little kid!" he announces proudly.

"Never mind that though, I have a snack for you! Would you like to eat this?" Her eyes dart to his sides and look down at a helpless body of a little boy.

"It's not like I like killing children you know? But I guess this is a necessary step for me to win this war."

She walks step by step to stand before a child's eyes. In his point of view, what he saw was not a terrifying demon, but a gorgeous woman stands before him. But that soon turns into fear.

"I'm sorry, but I had to do this."

Suddenly, the boy body jerk back as he feels a cold soft hand inside his body.

"Ugrwwwwwwwwwwww!"

"It would only hurt just a little bit, but it will calm down soon enough."

The boy body suddenly blows itself up into a particle of light. Every spectacle of blood and organ turn itself into a pure element. Including his blood from a floor, all disappear into nothingness and flow into caster body.

"What did you do?"

"You see, every living being in this world is made up from every kind of elements. One basic thing about elemental magic is that you need a source to use that element efficiently. This kid aptitude appears to be an earth element, so now I can use earth magic effectively."

"Wow, so what you're saying is that you can clean up my arts after I'm done with them. That's so cool!"

"It's not that cool actually, this the most basic of basics that I can do. I still have tons of trick that I could offer you, master."

"Wooo! I will follow you then! Please show me more! I don't care about what you're here to do. But let me follow you!"

"Alright, master. But first, I think we should get out of here before the polices come. Here, follow me."

She waved her hand, and a portal door to another realm was open before Ryunnosuke eyes. What he witnesses was something out of this world. He couldn't even believe something like that could have existed even if he was summoning a demon herself.

"Welcome to my great unmoving library, master."

…..

Kayneth was not pleased, to say the least. To think that his supposed servant was stolen by his own student and was used in war as his own. He will not accept this, he already came this far, and he will not back down from a single nuisance like him.

He was hoping that he could still get a servant with significant power despite having no catalyze right now. But that hope is diminishing every second as he waits for smoke to clear above the summoning sign.

A woman appears to be no older than her 20s was walking out when the smoke clears just as natural as the flow of water. She has a red hair, wears some kind of eastern cloth and hangs a scythe on her shoulder.

"Hm hm hm. Is this guy my master then? Wow, I can't say I'm impressed."

If Kayneth had any doubt before, it turns into a spiral toward hell. What did he just summon, and her personality is unbelievable. Was she insulting him in their first meeting? How insolent!

"Shut up! You are my servant, and you need to listen to me as your master."

"Yeah yeah, regulation and all that stuff, servant Lancer at your service."

"Well lancer, if you want to win this war, you need to follow my every command. Do you understand."

"What? If I don't do as you say, will you use that command seal to order me around? Nah, I don't think you be that stupid to use it on me every time you know?"

If he wasn't angry before, he was pissed now. How dare this servant talk back to him like that. His hand was slowly rising, and a bright red light covered the rune in his arm.

"Lancer! You will learn of your insolent and respect me. I order you t-"

"You can stop right there, Kayneth. Lancer, you too, stop teasing him."

"Aw man~ Did you see a look on his face? That was kinda funny."

A woman beside him was Sola-Ui, his soon to be wife. She was one person that Kayneth hold dear to his heart the most beside practicing magecraft. When he heard her voice, it calms him down to a point where he put down his hand and take a deep breath.

"Lancer, Prepare yourself. We will go out in a few minutes."

"Alright, but let me do my own thing, okay?"

"No"

…

"Father, all servant has already been summoned."

"That's good, now we can actually begin the holy grail war! We should execute our plan too, Kirei."

"Yes, father."

 **Chapter 2 end**


End file.
